Editor's Note: Mona Charen is off. The following is a column by Jamie Stiehm.

What a difference a mayor makes -- for better or worse. Houston, Texas, New Orleans, Louisiana, and Charlottesville, Virginia, residents have learned that fact real good.

Houston's mayor, Sylvester Turner, has not come through Hurricane Harvey with flying colors. Granted, to see a massive city drown on your watch in a Biblical flood is a tragedy beyond belief. We thought it couldn't happen here. Americans, particularly Texans, have a bravado that convinces us we're invincible.

Turner fatefully decided not to order the fourth-largest city to evacuate when the eye of the storm loomed off the Gulf Coast. Like a general fighting the last war, he sought to avoid deaths amid huge traffic jams, which happened in Hurricane Rita 12 years ago. When Texas Gov. Greg Abbott urged Houston residents to "strongly consider evacuating," the mayor sent out a contradictory tweet, directing people to stay home.

That's not the clear leadership we need now, as global warming comes home to haunt us. "We asked people to prepare, and they did," Turner said, dismissing social media and "talking heads."

Confronted with the catastrophe still unfolding now, Turner sticks by his story. His defiant tone, under duress, falls flat. It seems clear now that those living in Houston's 100-year floodplain should have been strongly encouraged to flee their homes, ahead of time, in an orderly process. That's emergency preparedness 101.

Frail and sick people, too, should have been spared the harrowing boat rescues provided by kind people acting as good Samaritans. They were largely from "civil society," not the government. Without an armada of volunteers, many more lives would have been lost.

If you've ever been to Houston, now a rainfall of tears, its character resembles a checkerboard that expanded like crazy. The master plan was to have no plan. The city's tragic chorus went like this:

"Global warming? Not today. Hey -- gotta go build another petrochemical complex and pave roads over more wetlands in the 'city without limits.' Zoning? No, sir, not here."

The beguiling city of New Orleans was drowned by a tempest 12 years ago. The Democratic mayor, Mitch Landrieu, issued a sympathetic statement this week: " No city welcomed more New Orleanians following (Hurricane) Katrina than Houston, and our heart breaks for them right now."

That sounds like a leader to me.

Landrieu, a scion of an old political family, took the courageous step of taking Confederate statues down this spring. In a surpassing speech, he said, "I knew that taking down the monuments was going to be tough, but you elected me to do the right thing, not the easy thing."

He called on New Orleans to "choose a better future for ourselves, making straight what has been crooked and making right what was wrong."

The new mayor of Baltimore followed suit without the speech. Catherine Pugh had four Civil War statues removed overnight this summer. One figure was Roger Taney, the former chief justice of the Supreme Court who authored the hateful Dred Scott ruling that blacks, free or enslaved, could never be citizens.

But in Virginia, where Confederate Gen. Robert E. Lee was master of a slave plantation called Arlington, the nation witnessed a Robert E. Melee.

The shocking Charlottesville bloodshed claimed the life of a civil rights activist, Heather Heyer. This was never a peaceful rally round the Lee statue. Armed Confederates, or white male supremacists, came to hurt people, and many counter-resisters were badly beaten.

What did the police do? Too much of nothing. The clashes were too violent.

What did the mayor say? Not much. Poor Michael Signer has no power over the police chief and the city manager. He was vexed, understandably, that he was blocked from the city command center. He found no words people needed to hear. His own synagogue was not protected by police.

Charlottesville leadership choked in an hour of crisis. Houston's mayor is not finding meaning in the flood, a takeaway lesson learned for the future.

Mayor Landrieu showed us what's all about, words and music.

What a difference a president makes. We Americans are all in that crucible together.